A law firm representing Britons alleged to have suffered from their use of the painkiller Vioxx is preparing to submit clients' medical records to US doctors.
Christine Peckham was among 500,000 Britons who used Vioxx
After a US jury found Merck, the drugs' manufacturer, negligent in the death of a user, MSB Solicitors in Liverpool said thousands of Britons could sue.
The case of Lancashire woman Christine Peckham will be one of the first to be examined to see if Vioxx made her ill.
MSB said: "If a link can be established US attorneys will file the action..."
Ms Peckham, from Skelmersdale, Lancs, took the drug to relieve arthritic pain.
As a result of her use, she claims to have suffered two strokes, which left her partially paralysed, visually impaired and epileptic.
Lawyer Gerard Dervan said: "We hope to have Christine's case ready for trial within 12 to 18 months. This is the start of a long fight."
Britain's Legal Service Commission has decided not to fund any actions against Merck so the case is being fought in the US, where a no-win no-fee system would apply.
Vioxx, which was withdrawn last September amid safety concerns, was seen as a breakthrough in pain relief for arthritis sufferers because it did not have the same side effects as other drugs.
But it was taken off the market after a long-term study found that the risk of heart attacks and strokes was doubled if patients took the drug for 18 months.
The drug is known to have been taken by more than 20m people worldwide before it was withdrawn. Almost 500,000 Britons have used it.
It has been estimated that Vioxx could have caused 27,785 heart attacks or deaths since it was approved for use in 1999.
Worldwide, more than 4,200 lawsuits have been filed against Merck over the drug.
A jury in Texas on Friday awarded a $253.4m (£141m) settlement to the widow of the US man who died suddenly after using Vioxx.
It found Merck negligent in the death of 59-year-old Robert Ernst and the court also heard claims that Merck had played down safety fears about the drug for a decade.
But Merck has always maintained that it investigated the safety issues as soon as they arose. It said there was no scientific base for the US ruling and it would appeal.
After the ruling in Texas, Merck attorney Jonathan Skidmore said: "There is no reliable scientific evidence that shows Vioxx causes cardiac arrhythmia, which an autopsy showed was the cause of Mr Ernst's death."
Mr Dervan said the Texas case was a "shot across the bows" for Merck.